It is really difficult to find any info on this, so I give it a go here. As I understand it the prev version SMP-C had a pinted scale on the bezel. PO has LM hence the silver color. The new SMP should be in enamel and according to Omega it should be more durable than the prev printed version... The printed scale on the old one could be worn off speaking from own experience. How is this enamel in this regard?

 

The first generation of SMP had the aluminum bezel insert with printing.
The second generation (SMPC) had a metal scale into ceramic. I do not know which metal is it, nor why Omega did not call it liquidmetal, but I am sure it is metal.
The third generation SMPC has enamel, I do not know about its durability.

 

The first two generations of SMP were aluminum bezel (first with painted logo and markers, 2nd with applied logo and markers). The 3rd generation had a ceramic bezel and the numbers on the bezel weren't metal since they could scratch and wear out. No idea about the durability of the enamel in the current 4th gen SMP but SMPs have never had metal numbers in the bezel.

Only the current generation of the Planet Oceans (and one of the LE) have liquid metal in the bezel. The Seamaster 300 Master Co-axial also has liquid metal in the ceramic bezel.

 

I consider 1120 and 2500 non-ceramics as a one generation.
Why do you think the numbers in SMPC were not metal?

 

This is the thread on WUS. A Scotchbrite pad will take the numbers off the SMPC bezel.

https://forums.watchuseek.com/f20/help-seamaster-ceramic-bezel-issue-771858.html